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Oct. 17, 1967 E. GERLACH Re. 26,283 DEVICE FOR CONTROLLING EQUENCY DURING TUBE FILM 3 Sheets-Sheet 1 THE IMAGE FR THE PROJECTION OF A MOTION PIC Original Filed May 29, 1962 Oct. 17, 1967 E. GERLACH Re. 26,283

DEVICE FOR CONTROLLING THE IMAGE FREQUENCY DURING THE PROJECTION OF A MOTION PICTURE FILM Original Filed May 29, 1962 3 Sheets-Sheet 2 E. GERLACH Re. 26,283 L EQUENCY DURING Oct. 17, 1967 DEVICE FOR CONTROL INC} THE IMAGE FR I THE PROJECTION OF A MOTION PICTURE FILM Orlglnal Filed May 29, 1962 3 Sheets-Sheet United States Patent Ofiice Re. 26,283 Reissued Oct. 17, 1967 ABSTRACT OF THE DISCLOSURE A film feeding mechanism for a projector wherein a film claw moves longitudinally along the film at a constant frequency with electrically actuatable into and out of engagement with the one of a plurality of dz'flerent frequencies.

which in dependence of the claw is being opened and closed.

With these now be described in connection 5 and a worm gear pivotally mounted with one of their ends pivot pins 7 and 8 and are provided intermediate their ends with flanges 11 and be held in constant engagement with the circumferences of the eccentrics 4 and 5 by means of a coil spring 19' connected with its ends to the levers 9 and 10, respectively. The free respect to their supporting rods 15 and 16 and extend lengthwise of the film 21. The claws 17 and 18 which are rotatably mounted on the pivot rods 15 and 16 are subsprings 19 and 20 which in invention are arranged on the pivot rods 15 and 16 between the bearing blocks 13 and 14 and the respective claws 17 and 18. The action of the torsion springs 19 and 20 is such that they try to rotate the claws 17 and 18 toward the motion picture outer ends of the claws 17 and 18 are provided each with a tooth 22 and 23 and adjacent of these teeth is arranged a horizontally extending projection 24 and 25 which are in engagement with one-armed levers 26 and 27. Each one-armed lever 26, 27 is fixedly attached to one end of shafts 28, 29 which are fixedly attached thereto between and 31. The shafts 28 and 29 are rotatabiy supported in axially spaced bearing 32, 33 and 34, 35 respectively. The free ends of a manner that the magnetic plates 30 and 31 are caused to be moved away from the electro-magnets 36 and 37. The force of the springs 51 and 52 is such that the action of the torsion springs 19 and 20 is overcome. The magnetic plate 30 is associated with the electro-magnet 36 and the magnetic plate 31 is associated with the elcctro-magnet 37. Both electromagnets 36 and 37 may be connected selectively by a double throw switch 38 and a selector switch 39 and one of a number of switches 40, 41, 42, 43, 44 and 45 with a source of current 46. The double throw switch 38 and the selector switch 39 are manually operated. The control switches 40 to 45 are arranged within the operating range of control cams arranged on a control drum 47. For the sake of simplicity and an easier the invention,

gear worm 6 on the motor driven shaft 2.

The operation of the device of the invention is as follows:

The motor 1 drives continuously the shutter shaft 2 with the shutter blade 3 thereon, the eccentrics 4 and 5 and the Worm gear 6. As a result the guide levers 9 and 10 are continuously moved back and forth about the pivot pins 7 and 8 so that the film advancing device is periodically moved back and forth. As long as the two electro-magnets 36 and 37 remain tie-energized, the lateral projections 24 and 25 on the claws l7 and 18 slide back 82d forth along the top edges of the one-armed levers and 27 without causing an engagement of the teeth switch 39 are in the illustrated position, an electric circuit may be closed by selector switch 39, electro-magnet 37 gear 6 mounted on the shaft 49. Since now the electromagnet 37 will be energized, the magnetic plate 31 will be attracted by this electro-magnet and will cause a rotative movement of electro-magnet and will cause a rotative movement of the shaft 29. The magnetic plates 30 and 31 never touch the electromagnet but remain at a distance therefrom. As a result, the onearmed lever 27 is lowered and also the projection on the claw 18 is lowered and this results in a tensioning of the spring 52. At the same time the tooth 23 on the claw 18 enters into one of the perforations 21a of the film 21 so that the film 21 is moved a distance equal to one frame by the guide lever 10 which is moved by the eccentric 5 on the shaft 2. In FIGURE 1, the motion picture film 21 will be moved toward the left and this may be considered the forward movement of the film. At the end of this movement which is a distance of one frame of the film the control cam 48 will have passed the control switch 40 which now opens, the electro-magnet becames dcenergized and releases the magnetic plate 31 so that now the shaft 29 rotates quickly and the one-armed lever 27 jumps upwardly under the action of the spring 52 into the initial position. During this movement the tooth 23 on the claw 18 is raised from the perforation in the film and the latter stops its movement. Depending upon the number of the cams 48 within the range of the control switch, the tooth 23 will either not engage at all the perforations 21a of the film 21, or in order to move the film 21, it will engage the perforations 21a at each swinging period of the levers 9 and 10, or at every other swinging period of the levers 9 and 10, and so on.

In order to move the film backwardly, i.e. from the left hand side to the right hand side in FIGURE 1, it is necessary to change the position of the double throw switch 38. When this is done, the electromagnet 36 will be energized and the magnetic plate rotates the shaft 28 anti-clockwise. The one-armed lever 26 tensions the spring 51 so that the claw 17 with its extension 24 and its tooth 22 is moved downwardly under the action of the torsion spring 19. The control operation is performed by means of the same elements as heretofore. Accordingly, the invention provides means for moving the film 21 backwardly and the picture frequency during this backward movement may be changed as often as desired and this may take place during the projection of the images of the film onto the screen.

Since the double throw switch 38 and the selector switch 39 may be easily accommodated in a remote control unit, the device of the invention may be easily changed to a projection of a film which is remotely controlled.

It is also possible to employ in place of the plurality of control switches 40 to a single control switch 40 (FIGURE 3) which would have to be arranged slidably along the control drum 47 in order to perform at the same time the function of a selector switch.

Finally, it is also possible by means of other elements, for instance as shown in FIGURES 3 and 4 by means of a commutator and slide contact, to produce the impulse for the electro-magnet in dependence of the conveying movement of the claw.

What I claim is:

1. In a device for controlling the image frequency during the projection of a motion picture film, claw means adapted to be moved periodically lengthwise of the film and to be moved selectively perpendicular with respect to said film for entering into a perforation of said film during selected longitudinal movements of the same, motor driven shaft means, a pivoted guide lever arranged to swing in the same plane as said film to which said claw means is pivotally attached, a cam on said shaft means engageable with said guide lever for moving said claw means periodically in a direction lengthwise of said film, a lever arm engageable with said claw means for periodically moving said claw means into and out of engagement with a perforation of said film, an electro-magnet arranged in an electric circuit having a source of electrical energy for actuating said lever arm, said electromagnet being connected selectively to a selector switch in said circuit, a plurality of circuits for said selector switch each of which contains a normally open control switch, a cam carrying drum having a series of circumferentially spaced members engageable with said control switches for closing one of said selective control switches periodically, said cam carrying drum being operated by said motor driven shaft means, said claw means and lever arm being positioned in closely spaced relation to said film and arranged substantially parallel therewith.

2. in a device for controlling the image frequency during the projection of a motion picture film, two selectively operable claws adapted to be moved periodically lengthwise of the film, one for the forward movement and one for the backward movement of the same, motor driven shaft means, a pair of pivoted levers arranged to swing in the same plane as said film, one of said two claw means being pivoted on the free end of each pivoted lever to swing about an axis normal to the direction of film move ment, yielding spring means for urging said claws downwardly, actuating means on said shaft means engageable with said pivoted levers for moving said claws periodically lengthwise of said film, means for selectively and pivotally moving said claws perpendicular to said film for periodic engagement with a perforation in said film, said last named means including two electro-magnets, a circuit for each electromagnet having a source of electrical energy, there being one electro-magnet for the forward movement and one electro-magnet for the backward movement of said film, each of said electromagnets being connected in said circuit and adapted to be selectively connected by a double throw switch with an electric circuit containing a selector switch which has connected thereto a plurality of circuits each one of which contains a normally open control switch, the latter being alternately opened and closed, a cam carrying drum which is rotated by said motor driven shaft means, said drum having projections on said cams for engaging said control switch and closing said circuit to energize said electromagnet and move said claw means into a perforation in said film.

3. In a device for controlling the image frequency during the projection of a motion picture film, claw means adapted to be moved periodically lengthwise of the film and to be moved selectively perpendicular with respect to said film for entering into a perforation of said film during selected longitudinal movements of the same, a motor driven shaft extending in a direction perpendicular to said film, a guide lever adjacent said shaft movable in a plane parallel to said film, a cam on said shaft engageable with said guide lever for moving said claw means periodically lengthwise of said film, an actuating lever adjacent said claw means, yielding spring means for urging said claw means downwardly in engagement with a perforation of said film, yielding spring means for urging said claw means and actuating lever upwardly away from said film, an electro-magnet for actuating said actuating lever and claw means, an electric circuit for said electro-magnet, said electro-magnet being adapted to be connected selectively by a selector switch in said circuit, a plurality of circuits connected to said selector switch each of which contains a control switch, a cam carrying drum operated by said motor driven shaft, said cam carrying drum being provided with a plurality of sets of circumferentially spaced cams arranged one set next to the other, the cams of each of said sets being engageable with one of the control switches in said circuits to open and close a selected control switch of said plurality of circuits whereby one series of cams at a time is selected by said selector switch to be connected with its associated control switch in said circuit of said electromagnet.

4. In a device for controlling the image frequency during the projection of a motion picture film, claw means adapted to be moved periodically lengthwise 0f the film and to be moved selectively perpendicular with respect to said film for entering into a perforation of said film during selected longitudinal movements of the same, a motor driven shaft, a guide lever movable in a plane paralfor urging out of engagement with said film, an

he other, one of each contains a different number of cams.

5. A device according attracted by said energized electromagnet.

6. In a device for controlling the image frequency dursaid normally open periodic switches in circuit with said electro-magnet so that by the segments on said commutator ring the electrocontinuous reciprocating motion of back and forth along the film;

back and forth movement of by advance film through the projector;

a rotatable member having a plurality of different series of cam projections; and

means including switch means actuated by said series film claw into and out engagement with the film at a plurality of difierent frequencies.

comprises an electro-magn et.

9. An intermittent film feeding mechanism for a film projector, comprising:

electrical switch means including a rotatable member having a plurality of different series of conductive one brush contact coacting with said series of segments for selectively actuating said electrically actuatable means to move said film claw into and out of engagement with the film at a plurality of difierent frequencies.

10. An intermittent film feeding mechanism as defined in claim 9, wherein said electrically actuatable means comprises an electrO-magnet.

11. An intermittent film feeding mechanism for a film projector, comprising:

a film claw;

means for eflecting continuous reciprocating motion of said film claw back and forth in a path generally parallel to the longitudinal axis of the film; electromagnetic means efiective upon energizanon thereof for moving said film claw into vancing the film; means including a plurality of electrical switch means for energizing said electromagnetic means at a plurality of difierent frequencies respectively; and means for rendering selected Ones of said plurality of switch means operative to control energization of said electro-magnet.

tive to control energization of said electro-magnetic means comprises a selector switch for selectively connecting said switch means in an electrical circuit with said electromagnetic means.

13. An intermittent film feeding mechanism as defined in claim I], wherein said said brush contacts in an electric circuit with said electromagnetic means.

14. An intermittent film feeding mechanism for a film projector, comprising:

means for effecting continuous reciprocating back and forth motion of said film claw along the film at a predetermined rate; electro-magnetic means effective upon energization thereof to move said film claw into and out of engagement with the film in synchronism with the back and forth movement of said film claw for advancing the film; means including a plurality of electrical switch means for energizing said electro-magnetic means at a pulrality of different frequencies respectively; and

means for remotely rendering selected ones of said plurality of switch means operative to control energization of said electro-magnetic means.

15. An intermittent film feeding mechanism as defined in claim 14, wherein the last said means comprises a manually operative selector switch means for selectivtly connecting said plurality of switch means to control energization of said electro-magnetic means.

16. An intermittent film feeding mechanism as defined in claim 15, wherein said means including a plurality of electrical switch means comprises a rotatable member having a plurality of different series of cam projections for actuating said electrical switch means between open and closed positions at said plurality of different frequencies.

17. An intermittent film feeding mechanism as defined in claim 15, wherein said means for energizing said electro-magnetic means comprises a rotatable member having a plurality of different series of conductive segments and a plurality of contacts coacting with said series of segments respectively.

18. An intermittent film feeding mechanism for a film projector having a voltage source, comprising:

a film claw;

means for effecting continuous back and forth movement of said film claw along the film;

an electro-magnet effective upon energizing thereof for moving said film claw into and out of engagement with the film in synchronism with back and forth movement of said film claw for advancing the film;

means including a plurality of electrical switch means for energizing said electro-magnet at a plurality of difierent frequencies respectively; and selector switch means for selectively connecting said switch means in series with said electro-magnet and the source to effect energization of said electromagnet at selected ones of said frequencies.

19. An intermittent film feeding mechanism as defined in claim 18, wherein said means including a plurality of electrical switch means comprises a rotatable member having a plurality of difierent series of cam projections for opening and closing said plurality of electrical switch means at different frequencies and said selector switch means comprises a selector switch.

20. An intermittent film feeding mechanism as defined in claim 18, wherein said means including a plurality of electrical switch means comprises a rotatable member having a plurality of different series of conductive segments and a plurality of contacts coacting with said segments, and said selector switch means comprises a selector switch.

21. In a device for controlling the image frequency during the projection of a motion picture film, claw means adapted to be moved periodically lengthwise of the film and to be moved selectively perpendicular with respect to said film for entering into a perforation of said film during selected longitudinal movements of the same, motor driven shaft means, a cam on said shaft means for moving said claw means periodically in a direction lengthwise of said film, an electromagnet arranged in an electric circuit having a source of electrical energy for actuating and moving said claw means into and out of engagement with a perforation of said film, said electro-magnet being connected selectively to a selector switch in said circuit, a plurality of circuits for said selector switch each of which contains a normally open control switch, a cam carrying drum having a series of circumferentially spaced members engageable with said control switches for closing one of said control switches periodically, said cam carrying drum being operated by said motor driven shaft means.

References Cited The following references, cited by the Examiner, are of record in the patented file of this patent or the original ALLEN N. KNOWLES, Primary Examiner. M. I-IENSON WOOD, JR., Examiner. 

